Issues

15 is the speed sensor and 21 is O2 sensor not giving feedback for a set time frame. Could be why it puffed some blue. Most likely it was rich because of the o2 not correcting the a/f ratio.

Could it be possibly the timing? when we fixed the intermediate shft, we really just put it back together quick and werent 100% sure how to set the timing, the car is missing the cover that has the point of reference on it. If it isnt the timing, why wouldnt it be correcting a/f, gone bad or something?

The real point of reference for the cam are the 2 arrows on the sprocket pointing to the parting lines on the cam caps. Then the dot and the line in the int shaft cog line up with each other at 0^ on the flywheel. the distr is then set with the rotor pointing at #1.

Another thing to do is take a small punch and gently put a mark on the valve cover through the small timing hole in the cam sprocket. Then you can look through it to line things up easily.

well he set the timing to 11, still getting the popping in the exhaust, havent drove it around yet and we reset the codes. 21 doesnt show up now, but like I said, I havent driven it yet.

no more popping, engine light didnt com on till I got onto the freeway but I didnt pay attention to when exactly it came on.